This invention relates to particularly efficient methods for producing bioactive suspensions. Typical areas of application in biotechnological, cosmetic and pharmaceutical production, therefore, are disintegration of cells of different origin, such as yeasts, bacteria, etc., and the recovery of cell contents, such as enzymes, nucleic acids and other physiologically active materials.
Suitable methods for producing bioactive suspensions can basically be divided into conventional mechanical methods and methods in which ultrasound is employed.
Up till now, only conventional mechanical methods, which usually comprise equipment for mechanical destruction, have reached industrial importance. Such equipment includes especially ball mills, mortars and extrusion homogenizers. The method steps given in DE 3,139,093, DD 216,628 and DE 3,515,231 relate primarily to comminuting methods with ball mills, temperature regimes staggered timewise and intensive stirring, which is employed additionally.
In DE 3,226,016, an installation with an extrusion homogenizer is described, in which the cells are destroyed by a high pressure gradient and cavitation and turbulence effects in a narrow gap.
It is a fundamental disadvantage of these methods and arrangements that they are very time-consuming and that the result of the disintegration is unsatisfactory. It is also disadvantageous that, in many cases, only organic compounds, which are stable over time, can be treated. Moreover, the above-mentioned mechanical methods are very energy-intensive, are responsible for high plant and operating costs and their efficiency remains restricted to a few substances of lesser resistance.
Of the possible methods of disintegration, in which ultrasonic equipment is employed, only a few are known from the literature and the brochures of manufacturing companies, which are restricted to laboratory applications. The characterizing feature of this method is the known arrangement of an ultrasonic facility, which comprises an HF generator, an electromechanical transducer with operating tool (sonotrode) and a plurality of generally open sonication vessels, which moreover, can be cooled and to which medium can be supplied continuously.
Special sonicators (cells) are also known from DE 2,027,533 and DD 2,836,741, which sonicators are coupled directly to an electromechanical ultrasonic transducer. It is a disadvantage of these sonicators that, due to the necessary construction as a wavelength-dependent resonator element, the sonicator may not be constructed of such volume that cooling is possible.
Many sonotrode shapes, suitable for sonication, are known from the technical specifications of inventions. It is a decisive disadvantage of these methods and arrangements that the result is insufficient disintegration of not more than 60%. Such a low result is due to the fact that no means for favoring the ultrasonic effect are employed and that the necessary design dimensioning of an effective sonication volume is not taken into consideration.
It is an object of the invention to provide a method and appropriate equipment for the preparation of bioactive suspensions by means of high-power ultrasound and to achieve the best possible disintegration result at little cost.